Seattle, Washington
South Park Roadway and Drainage Partnership Project
The South Park industrial area has been impacted by overland flooding from the Duwamish River and localized flooding from an undersized and inadequate public storm drain system. This Osborn-led project’s goal was to reduce flooding by installing more than 4,000 LF of new public storm drainage system and improve transportation with construction of approximately 1.5 lane miles of new right of way improvements, including sidewalks, trees, and roads designed for the industrial uses. Today, the neighborhood is safer with transportation improvements, healthier with the addition of trees and vegetation, and more productive with the reduction in frequency of flooding events.
Owner
Seattle Public Utilities
The team analyzed preliminary options to address the flooding and roadway condition concerns, completed initial storm sewer sizing and layouts for several options, and worked with the City, the community, and other stakeholders throughout the preliminary engineering process to identify their project values and potential impacts. The solutions included a new piped conveyance system and new sidewalks with planting areas, resulting in improvements to the right-of-way over several blocks.
Osborn led an options analysis workshop with SPU and SDOT representatives, which considered criteria such as constructability, maintenance, climate change, property impacts, and social equity factors from public outreach. The preferred alternative included planning for new bus stop facility locations, as well as pedestrian safety design in a tight ROW with industrial traffic. Sidewalks were provided behind landscape strips and adjacent short asphalt wedges were used in some locations to minimize property impacts while still providing a separated sidewalk along the right-of-way for public safety.
Prior to construction
Post-construction
Post-construction
